The Clinical Science Research Core (CSRC) enhances and facilitates nutrition/obesity-related clinical translational research by assisting investigators in conducting studies in human subjects through the operation of two sub-cores. The Clinical Studies Performance sub-core facilitates clinical research by assistance with: i) subject recruitment, ii) planning and performance of clinical studies, iii) collection of fat and muscle tissue samples, iv) exercise testing, v) lifestyle intervention, vi) whole-body and regional body composition assessments (DEXA, MRI, MRS), vii) indirect calorimetry, and viii) assessment of cardiovascular structure and function. The Metabolic Kinetics sub-core provides comprehensive state-of the- art stable isotope labeled tracer and non-tracer applications to study diverse areas of metabolic function (production/synthesis and catabolic rates; insulin sensitivity, beta-cell function). In addition, the CSRC provides training for investigators, their staff, and research fellows in these areas of clinical research, both in the form of one-on-one hands-on instruction as well as through seminars and lecture series. Combining these services within one Core provides a cohesive organizational structure that facilitates the performance of complex clinical research studies, fosters interdisciplinary collaborations between NORC investigators, and reduces the barriers for basic scientists and young investigators who wish to conduct clinical research.